Bucket attachment for wheel loaders



Sept. 1, 1970 N. L; ANDERSON ETAL 2 BUCKET ATTACHMENT FOR WHEEL LUADERS Filed Sept. 26. 1967 5 Sheets-Sheet 1 INVENTORS NORMAN L. ANDERSON HOWARD B. AUSTIN DORRANCE OLDENBURG JACOB E. STAAB ROBERT N. STEDMAN Armmms x 1 Sept. 1, 1970 L ANDERSON ETAL 3,526,329

BUCKET ATTACHMENT FOR WHEEL LOADERS Filed Sept. 26. 196? 3 Sheets-Sheet B INVENTORS NORMAN 1.. ANDERSON HOWARD a AUSTIN DORRANCE OLDENBURG. JACOB E. STAAB BY ROBERT N. STEDMAN United States Patent G 3,526,329 BUCKET ATTACHMENT FOR WHEEL LOADERS Norman L. Anderson, Peoria, Howard B. Austin, East Peoria, and Dorrance Oldenburg and Jacob E. Staab, Peoria, and Robert N. Stedmau, Chillicothe, 111., assignors to Caterpillar Tractor Co., Peoria, 111., a corporation of California Filed Sept. 26, 1967, Ser. No. 670,676 Int. Cl. E02f 3/70 US. Cl. 214-140 2 Claims ABSTRACT OF THE DISCLOSURE A bucket loader attachment for rearward mounting on a standard wheel loader vehicle of a type which is normally free to oscillate on its rear axle and which has a standard forward bucket. A frame pivotally supporting a bucket on lift arms is connected to the rearward framework of the vehicle. Hydraulic jacks are interposed be tween the frame and the lift arms and between the frame and the bucket to respectively control elevation and tilting of the bucket. Stabilizing means are provided which are operable to prevent undesirable oscillation of the vehicle caused by the rear bucket loader.

Wheel loaders of a type having a forwardly mounted bucket are limited in load carrying capacity due to the feasible size of the single bucket and more importantly their maximum capacity is limited by the weight which the vehicle can support in the single bucket without causing instability or tipping of the machine. Such capacity limitations have been particularly noted in quarry operations where such loaders are used to feed crushers which are set up at an established site. As the rock loading site becomes remote from the crusher, the limited capacity of the loaders necessitates the use of trucks to carry the rough rock from the loader to the crusher. Use of the additional equipment is undesirable since it substantially reduces the efiiciency of the quarry operation.

The present invention overcomes the above problem by providing an implement attachment which may be mounted on the wheel loader at its opposite end from the standard bucket assembly. The attachment is of mechanically simple construction and is suitable for unitized mounting upon a standard wheel loader, thus reducing the capital expenditure necessary to practice the invention. In addition to the above advantages, the use of a bucket assembly on either end of a standard wheel loader permits an increased capacity in each bucket since they balance each other thus adding to the stability of the vehicle.

Such standard wheel loaders often include means permitting the vehicle to oscillate upon its rear axle. With a bucket attachment connected to the rear of the vehicle, this oscillating freedom is undesirable since it allows sidewise tipping of the machine when the rear bucket is loaded and also induces stresses in the wheel loader vehicle. To further increase the stability of the wheel loader, the present invention also contemplates stabilizing means for association with the oscillating means of the vehicle with the stabilizing means being operable to prevent oscillation of the vehicle upon is rear axle at least when the rear bucket attachment is being employed.

Additional advantages and features of the present invention are made apparent in the following description and the accompanying drawings wherein FIG. 1 is a side elevation of a standard wheel loader with the present bucket loader attachment rearwardly disposed thereon;

FIG. 2 is an illustration of the rearmost portion of the wheel loader vehicle and of the bucket loader attachment;

3,526,329 Patented Sept. 1, 1970 FIG. 3 is a partial plan view, with parts in section, of the wheel loader vehicle illustrating the means for permitting oscillation of the vehicle upon its rearward axle; and

FIG. 4 is a fragmentary front elevation view which illustrates the oscillating means in greater detail.

A standard wheel loader vehicle of articulated construction and having a forwardly disposed bucket 11 is illustrated in FIG. 1 with a bucket loader attachment, generally indicated at 12, disposed at its rear. As is more clearly shown in FIG. 2, the vehicle has a rearwardly extending portion 13 of its main framework with an engine contained in a compartment 14 supported thereupon. The bucket loader attachment comprises a frame 16 suitable for connection to the rearwardly extending framework of the vehicle with a bucket 17 pivotally supported thereon by means of a pair of lift arms, one of which is indicated at 18. Motor means for controlling the bucket position include a hydraulic jack 19 pivotally connected between the frame and each lift arm for varying elevation of the bucket and a pair of hydraulic jacks, one of which is indicated at 21, pivotally connected between the frame and each side of the bucket for varying the tilt position of the bucket.

As is shown in FIG. 2, the bucket attachment frame comprises a bottom plate 22, outer and inner side plates 23 and 24 at each side of the frame extending upwardly therefrom and a formed top plate 25 connected between each pair of outer and inner side plates. The attachment frame surrounds the main framework and engine assembly with the bottom plates and side plates being secured to the main framework by bolt 26. Each lift arm is pivotally secured to the side plates by a pivot pin 27 and to the bucket by another pivot pin 28. Each lift jack 19 is pivotally connected between brackets 29 and 31 located respectively on one of the outer side plates and the lift arms. Each tilt jack 21 is trunnion mounted between one of the inner and outer side plate pairs at 32 with its rod end 33 pivotally connected to the bucket at 34. The bucket 17 is illustrated in a loading position while retraction of both the lift jacks and tilt jacks causes the bucket to assume a carry position indicated at phantom position 17'. For dumping of the bucket, the tilt jack is extended to tilt the bucket forwardly from its carry position.

The present bucket loader attachment permits rapid and simple conversion of a standard wheel loader to provide a bucket at both ends thereof. While the addition of the bucket loader attachment doubles the load carrying capacity of the standard wheel loaders, it is to be noted that the capacity of each bucket may be still fur ther increased since the two buckets tend to balance each other and increase the stability of the vehicle. It is further to be noted that such wheel loaders are employed commonly with the bucket partially raised from its loading position and tilted forwardly such that its floor 36 is generally vertical to the ground to provide for bulldozing action, for example, during cleanup operation. Thus, it is apparent that the attachment frame 16 may be employed to support other earthworking implements such as a bulldozer blade.

Such wheel loader vehicles are commonly supported by a rear axle 37 upon a pair of wheels 38 with the vehicle free to oscillate about a center pivotal connection (not shown) with the rear axle.

With the rear bucket loaded, the oscillating freedom of the vehicle is often undesirable. To prevent this undesirable oscillation and stabilize the vehicle during use of the rear bucket attachment, stabilizing means are employed in the form of a pair of hydraulic cylinders 39', each connected between the vehicle and one end of its rear axle. A conduit 44 connecting the rod ends of the cylinders and a conduit 46 connecting their head ends permit transfer of fluid between the cylinders during oscillation. A "valve represented at 47 is closed to prevent such transfer and thereby stabilize the vehicle while the rear loader is in use.

We claim:

1. A loader machine adapted for combined loading and transporting, comprising a vehicle having an operators station a pair of like purpose buckets of substantially similar load carrying capacity, each said bucket being pivotally mounted on an opposite end of the vehicle for translatory movement confined to a vertical path, and

means for separately operating the buckets from the station and permitting the buckets to be successively loaded and raised into similar transport positions wherein the two buckets end to balance each other with respect to the vehicle in both loaded and empty conditions,

whereby the balanced positioning of .the two buckets enables the vehicle to accept increased loads and to operate with substantially increased efliciency over extended transport distances, the buckets being arranged in outwardly facing relation from the vehicle and including cutting edges whereby one bucket may be loaded during forward operation of the vehicle and the other bucket may be loaded during reverse operation of the vehicle.

2. In a transport type bucket loader vehicle having one bucket pivotally supported at one end of the vehicle for translatory movement confined to a vertical path, the one bucket having an opening facing away from the vehicle to permit loading of material into the one bucket,

and motor means for operating the one bucket in said confined path to suitable loading, transport and dump positions,

another like purpose bucket of substantially similar load carrying capacity similarly pivotally supported at an opposite end of the vehicle from the one bucket, the other bucket being arranged in oppositely facing relation with respect to the one bucket, and motor means for operating the other bucket in a similar confined vertical path into suitable loading, transport and dump positions independently from operation of the one bucket, the respective motor means for the two buckets permitting them to the successively loaded and raised into similar transport positions with the two buckets tending to balance each other upon the vehicle in both loaded and empty conditions, the balanced positioning of the two buckets enabling the loader vehicle to accept increased loads and to operate with substantially increased efiiciency over extended transport distances.

References Cited UNITED STATES PATENTS 2,663,266 12/1953 Baldwin 280-111 X 2,718,318 9/1955 Schmucker et a1. 214766 X 2,874,489 2/1959 Orjala 21414() X 3,349,932 10/1967 Wagner 214-138 2,890,805 6/1959 Pilch 214-438 3,047,170 7/1962 Hough et a1. 214131 3,129,832 4/1964 Metailler 214-138 HUGO O. SCHULZ, 'Primary Examiner 

